Patent application number | Description | Published |
20090147336 | OPTICAL SCANNER AND COLOR IMAGE FORMING APPARATUS - An optical scanner is disclosed that has an optical source unit that emits a laser beam; a vibration mirror by which the laser beam from the optical source unit is deflected to scan; a driving circuit that vibrates the vibration mirror based on a driving signal generated from a reference clock; a light-receiving element that receives the laser beam within the scanning area of the laser beam; and a controlling unit that corrects the driving signal so as to make a phase deviation between the reference phase clock and the output signal of the light-receiving element constant. | 06-11-2009 |
20120068643 | Motor driving device - A motor driving device driving coil terminals of a three-phase motor to flow three-phase currents includes: a pulse modulator generating three-phase modulation pulses, each of which has a duty ratio in accordance with a voltage level of a coil terminal; a shift amount selection unit selecting a first shift amount corresponding to at least one of two predetermined amounts according to a pulse width of the longest pulse among the three-phase modulation pulses; a first shift unit shifting the second-longest pulse among the three-phase modulation pulses backward by the first shift amount to delay timing; a second shift unit shifting the third-longest pulse among the three-phase modulation pulses backward by a predetermined second shift amount to delay timing; and an inverter driving each of the coil terminals by switching a driving power supply with the three-phase modulation pulses by reflecting shift results of the first and second shift units. | 03-22-2012 |
20120306419 | MOTOR SPEED CONTROLLER AND CONTROL METHOD - A motor speed controller controls a motor speed to generate a phase reference pulse; generates a FG pulse per rotary angle of the motor; detects a difference between the number of phase reference pulses and the number of FG pulses for output as an integer number phase difference; detects and measures a time difference between an edge of the phase-reference pulse and an edge of the FG pulse in units of the reference clock for output as a decimal fraction phase difference; adds the integer number phase difference to the decimal fraction phase difference at a predetermined ratio for output as a phase difference; and controls driving of the motor in accordance with the phase difference. | 12-06-2012 |
20130099708 | ANGLE DETECTION DEVICE, MOTOR DRIVING DEVICE, AND IMAGE FORMING APPARATUS - Disclosed is an angle detection device including plural sensors that output corresponding sinusoidal signals, wherein each of the sinusoidal signals varies sinusoidally depending on a rotational angle of a rotor of a motor, and each of the sinusoidal signals has a phase that depends on a position of the corresponding sensor; a vector generating unit that generates a vector represented by a result of mutually operating at least two of the sinusoidal signals; a vector rotation unit that rotates the vector by operating the vector and reference sine waves having corresponding phases; and an angle search unit that causes the vector rotation unit to sequentially rotate the vector until a phase of the vector becomes a predetermined phase, and that detects an angle between the vector prior to being rotated and the predetermined phase as the rotational angle of the rotor of the motor. | 04-25-2013 |
20130106326 | MOTOR DRIVE CONTROLLER AND CONTROL METHOD | 05-02-2013 |
20130106327 | MOTOR DRIVE CONTROLLER AND CONTROL METHOD | 05-02-2013 |
20130257341 | MOTOR CONTROLLER AND MOTOR CONTROL METHOD - A motor controller receiving as input an encoder signal changing in response to a driving position of a motor, outputting a motor driving command in response to the encoder signal to control at least one of the driving position or a driving velocity of the motor, includes an interrupt processing section to execute interrupt operations every prescribed interrupt cycle, a low-frequency processing section to selectively execute a subset of the interrupt operations every prescribed number of the interrupt cycles, and a high-frequency processing section to execute another subset of the interrupt operations every prescribed interrupt cycle, wherein the high-frequency processing section executes at least an operation to detect the driving position indicated by the encoder signal, wherein the low-frequency processing section executes at least an operation to generate the motor driving command. | 10-03-2013 |
20140258580 | MOTOR CONTROL APPARATUS AND MOTOR CONTROL METHOD - A motor control apparatus includes: a driving control unit that performs driving control of a motor in accordance with a drive command; an interrupt control unit that starts and executes interrupt processing for performing the driving control at an interrupt cycle; a first processing unit that executes same first processing every time the interrupt processing starts; and a second processing unit that selects and executes a different piece of processing from second processing every time the interrupt processing starts. The interrupt control unit executes at least one piece of the first processing before executing the second processing in the interrupt processing. | 09-11-2014 |
20140354202 | MOTOR CONTROL DEVICE - A motor control device controls a speed of a motor. The motor control device includes: a target speed generating unit that generates a target speed; a speed detecting unit that detects a current speed of the motor; a speed comparing unit that compares the target speed with the current speed to calculate a speed error; an error amplifying unit that amplifies the speed error and outputs a control value; and a motor driving unit that drives the motor in accordance with the control value. The error amplifying unit has proportional integral characteristics by which the speed error is amplified with a proportional gain and integration is performed in a lower frequency range than an integral corner frequency, increases the proportional gain as the current speed is higher, and shifts the integral corner frequency to a lower frequency as the current speed is higher. | 12-04-2014 |